Desktop systems will apparently disable the Metro environment.

The mobile operating system, available for both ARM phones and tablets and x86 tablets, won't include a desktop environment at all. Laptop and desktop systems will have the desktop and will default to it. Hybrid systems are described as offering both a Metro-style mode and a regular desktop mode, governed by whether their keyboards are attached or available.

Neowin reports that Microsoft is going a step further, with the live tile-centric Metro mode disabled by default for desktop machines. Metro apps themselves will still be available, launched from a new hybrid Start menu, residing in regular windows.

Threshold is expected to come in the first half of 2015, possibly even as a free update to Windows 8.1 (and perhaps, Foley's sources speculate, Windows 7) users.

Between now and then, a second update to Windows 8.1 is believed to be in the works. Windows 8.1 Update 2 (for want of a better name) is expected to be a much less substantial update than the Windows 8.1 Update that was released in April and should make only small user interface adjustments.

Foley's sources say that the second update should be rolled out with the August Patch Tuesday release. A preview release of some kind for Threshold should be released to the public some time in the autumn.

Overall, it looks that just as Apple and Google are embracing (and even extending) Microsoft's type-centric, more geometric, skeuomorphism-free Metro design language, Microsoft is backing away from it, or at least, backing away from its most visible implementation. While the company is understandably gun-shy about pushing Metro—Windows 8 in particular was obviously rough and unfinished in a lot of ways, and that alienated many early adopters—backing away from the design concept just as it's going mainstream doesn't seem like the most forward-looking action.